Process of making and testing tube joints



Oct. 23, 1934. T. A. coRBY PROCESS OF MAKING AND TESTING TUBE JOINTS Filed Dec. 2, 1929 F/G.Z.

fiamas/i cany UNITED STATES PATENT OFFICE PROCESS OF MAKING ANDTESTING TUBE JOINTS Thomas A. Corby, Pol lhkeepsie, N. Y. Application December 2,1919, Serial No. 410,959 3 Claims. (01. 113-112) My invention relates; to joints between pipes Tubes and pipes joined in the way described or tubes to make a lorig, continuous, fluid-tight and with every joint given an indlvidual test imconductor for, gases or liquids. The invention mediately after its completion may be submerged relates not only. to the joint itself, butgalso to in a river bottom or other inaccessible place with 5 the process of making thejoint and testing its every assurance of long continued service withfluid-tightness. out leaks.

The object of the invention is to provide 8. Though I have described tests of joints as being fluid-tight joint between tubes or pipes and also made by filling the annular space with gas under to so construct the joint that -it,.-may be immepressure, which I have found to be particularly to diately tested and,--i1' found defective, may be efiicacious for the purpose, it is obvious that any immediately cut out and'fthe ends again joined. fluid capable of being pumped against high pres- My improved joint, made and tested in acsure may be substituted for the gas without decordance with my invention, is particularly valparting from the spirit of my invention. uable for under-water or other conductors which, Having now fully described my invention, what 15 after they are in place, will be inaccessible for Iclaim and desire to protect by Letters Patent examination or repair. is:

In the drawing, which shows a joint made in 1. The process of uniting tubes which comprises accordance with my invention, Fig. 1 is a longiwelding together the opposing ends of the tubes, tudinal sectional view of the complete joint, and enclosing the joined ends of the tubes in a tubu- 2 Fig. 2 is an enlarged sectional view of the weld lar sleeve which overlaps the weld and whose inbetween adjacent tubes. ternal diameter is greater than the 'external a and b are ends of tubes which were to be diameter of the tubes, and welding the ends of the joined. 0 is a weld connecting the two tubes sleeve to the respective tubes so as to provide a together. at is a short section of a larger tube or narrow annular chamber surrounding the tubes 25 sleeve which is slipped over the joint and welded and adapted to receive fluid under pressure. 30 to the tubes at e and f. At 9' there is provided in 2. The process of uniting tubes and testing the sleeve d a small hole through which air or other tightness of the joints which comprises welding gas may be forced in at high pressure to test the together the opposing ends of the tubes, enclos- ,joint. ing the joined ends of the tubes in a tubular sleeve I 34)v In joining pipes or tubes according to my inwhich overlaps the weld and whose internal vention, the tubes a and b are first welded todiameter is greater than the external diameter of gether in the usual manner as shown at c. This the tubes, welding the ends of the sleeve to the weld is made with particular care because it will respective tubes and thereby providing a narrow be afterward inaccessible. The sleeve d is then annular chamber surrounding the tubes, filling 35 slipped over the joint and welded to the main said chamber with fluid under pressure, closing tubes as shown at e and f. The internal diamthe fluid inlet and observing the rate of fall of eter of the sleeve d should be somewhat greater pressure. than the external diameter of the main tubes 3. The process of uniting-tubes and testing the so as to provide a narrow annular space surtightness of the joints which comprises welding 40 rounding the main tubes. Through a small hole together the opposing ends of the tubes, enclosing g gas is forced to fill this space at high pressure. the joined ends of the tubes in a tubular sleeve After the space is filled the control valve is closed which overlaps the weld and whose internal and a pressure gauge in communication with the diameter is greater than the external diameter of space is watched. If the joint is tight at all three the tubes, welding the ends of the sleeve to the 45 welds the pressure will stay up for a long time. respective tubes n thereby p vi i a na r w If there is any leak it will drop rapidly. When annular chamber surrounding the tubes, filling the pressure drops during the test of any weld, said chamber with fluid under pressure, closing soap suds may be spread around the outer joints the fluid inlet and observing the rate of fall of l and any bubble formation will indicate the lopressure, thereby determining whether the welds 50 cation of any defect, which can then-be easily between the sleeve and the tubes are fluid-tight corrected. If, when there are no defects in the and, if found not to be fluid-tight, making them outer welds, the pressure does not stay up, it is so, and renewing said high pressure fluid test and proof that the inner weld is not tight. The tubes observation thereof to determine the tightness 01. are then cut off outside of the outer welds and a. the weld between the opposing ends of the tubes. 55 new joint made between the new ends. THOMAS A. CORBY; 

